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Background: Peperomin E (PepE) is a type of secolignan that is a major component of the plant Peperomia dindygulensis. It has been shown to exert anticancer effects in various cancer cell lines; however, the effects of PepE on human gastric cancer remain unexplored.Purpose: The aim of this study was to investigate the effectiveness of PepE as a treatment of gastric cancer and to identify the underlying mechanisms of its anticancer activity.Study Design: The efficacy of PepE was examined using human gastric carcinoma SGC-7901, BGC-823, MKN-45 cell lines and normal gastric epithelial GES-1 cell line as an in vitro model and SGC-7901 xenograft mice as an in vivo model.Methods: Cell viability assays were used to examine the anticancer effect of 0-204.8µM concentrations of PepE in vitro. Additionally, flow cytometry and western blotting were used to elucidate the mechanism with a particular focus on apoptosis. SGC-7901 cells were injected into BALB/c mice, which were then treated with 5 or 15mg/kg/day dose of PepE. The in vivo activity of PepE was investigated by measuring tumors and conducting immunohistochemistry experiments. The safety of PepE was investigated by measuring blood biochemical parameters and conducting histopathological analysis. Taxol was used throughout as a positive control.Results: The results showed that PepE exhibited antiproliferative effects against gastric cancer cells and induced their apoptosis in a dose dependent manner with lower toxicity against normal gastric epithelial cells. Mechanistic evaluations indicated that PepE induced apoptosis by reducing the mitochondrial membrane potential (MTP), inducing cytochrome C release from mitochondria, reducing the ratio of Bcl-2/Bax and Bcl-xl/Bad, increasing activation of caspase-3, and decreasing the levels of PI3K and pAkt. The apoptotic effect of PepE on SGC-7901 cells was partially blocked by an Akt activator SC79. PepE potently inhibited in vivo tumor growth with no obvious toxicity following subcutaneous inoculation of SGC-7901 cells in nude mice.Conclusions: These findings indicate that PepE can inhibit cell proliferation and induce apoptosis of gastric cancer cells through mitochondrial and PI3K/Akt signaling pathways with relative safety and may be a novel effective chemotherapeutic agent against gastric cancer. [ABSTRACT FROM AUTHOR]

Phytochemical investigation of the whole plants of Saururus chinensis resulted in the isolation of two sesquiterpenes ( 1 and 2 ), five lignans ( 3-7 ), one alkaloid ( 8 ) and two steroids ( 9 and 10 ). Among them, compound 3 has not been reported as a natural product before. Compounds 1 , 2 , 8 and 10 were firstly reported from the family Saururaceae. The possible biosynthesis pathway for sauchinone-like neolignans ( 6 and 11 ) was also firstly proposed. Furthermore, the chemotaxonomic significance of these compounds was summarized. [ABSTRACT FROM AUTHOR]

Highlights: [•] Three novel eudesmane sesquiterpenoid lactones were isolated and characterized. [•] One new diterpenoid was isolated and characterized. [•] Sesquiterpenoid lactones substituted at both C-1 and C-3 positions were reported. [•] One new compound exhibited cytotoxicity on HepG2 and MCF-7 cell lines. [Copyright &y& Elsevier]

Abstract: A novel securinega alkaloid, suffruticosine (1), was isolated from the leaves and barks of Securinega suffruticosa. The structure of 1, characterized by a fused complex octacyclic system, was elucidated by combined spectroscopic techniques, especially 2D NMR and CD spectral analyses. [Copyright &y& Elsevier]

A phytochemical investigation of Dictamnus angustifolius led to the isolation of 14 compounds, including six furoquinoline alkaloids ( 1 – 6 ), two sesquiterpenoids ( 7 , 8 ) and six flavonoids ( 9 – 14 ). The structures of these compounds were identified by spectroscopic methods and a comparison of their data with those reported in the literature. This is the first report of three furoquinoline alkaloids 1 – 3 and six flavonoids 9–14 from the genus Dictamnus and the first isolation of compounds 4 – 8 from D. angustifolius . The chemotaxonomic significance of furoquinoline alkaloids and sesquiterpenoids has also been summarized. [ABSTRACT FROM AUTHOR]

Abstract: Seven flavonoids (2, 4, 6, 10, 14–16), five phenolic acids (3, 5, 7–9), one monoterpene (11), two sterols (1 and 12) and an esters compound (13) were isolated from the whole plant of Alpinia Sichuanensis for the first time. Among them, compounds 7, 8 and 16, are reported from the family Zingiberaceae for the first time. The chemotaxonomic significance of these compounds was summarized. [Copyright &y& Elsevier]

Abstract This paper presents a direct method to establish a 3D elastoplastic constitutive model for soils based on the characteristic stress. In the established model, a new yield function is first formulated through an interpolation function in the characteristic stress space. A hardening parameter that suits for monotonic and cyclic loading conditions is established by introducing the concept of the subloading surface. Then, a 3D constitutive model for soils is established by combining the previously proposed plastic potential function. Only seven material parameters with clear physical meanings are included in the proposed 3D elastoplastic model. The deformation behaviours of soils under monotonic and cyclic loading conditions and the critical state properties under true triaxial stress conditions are analysed on the basis of the presented model. The capability of the model is verified by the comparisons between the model responses and the test results of soils under the 3D monotonic and cyclic loading conditions. [ABSTRACT FROM AUTHOR]

Five novel compounds, including four neoclerodane diterpenoids, named ajugacumbins K N ( 1 – 4 ) along with a phytoecdysterone, named ajugacetalsterone E ( 5 ), were isolated from the whole herbs of Ajuga decumbens (Labiatae). Their structures were elucidated on the basis of detailed spectroscopic analysis including IR, HRESIMS, CD, 1D and 2D NMR spectroscopic experiments. Compounds 1 – 5 were evaluated for their cytotoxic activities and the effects on superoxide anion generation and elastase release in FMLP/CB-induced human neutrophils. [ABSTRACT FROM AUTHOR]

Three novel limonoids, dictangustone G ( 1 ), dictangustone H ( 2 ), and dictangustone I ( 3 ) were isolated from the root bark of Dictamnus angustifolius . Their structures were elucidated on the basis of detailed spectroscopic analysis including UV, IR, HRESIMS, 1D and 2D NMR spectroscopic experiments. Compounds 1 – 3 were evaluated for their cytotoxic activities using Hela, A549, MCF7, and LN229 cell lines. [ABSTRACT FROM AUTHOR]

Abstract: Two new dimeric diarylheptanoids, named Alpinin C (1) and D (2), a new natural product of diarylheptanoid (3) along with three known diarylheptanoids (4–6) were isolated from the rhizomes of Alpinia officinarum Hance. Their structures were elucidated based on extensive spectroscopic analyses (1D and 2D NMR, HRTOFMS, IR). The isolated compounds were evaluated for their cytotoxicity against human tumor cell lines HepG2, MCF-7, T98G and B16-F10. Compound 1 showed selective cytotoxicity against cell lines of MCF-7 and T98G, while compound 6 showed significant cytotoxicity to the all tested tumor cell lines with IC50 in the range from 8.46 to 22.68μmol/L. [Copyright &y& Elsevier]

Abstract: Two new diterpenoid alkaloids, Guan-Fu base J (GFJ, 1) and Guan-Fu base N (GFN, 2) along with nineteen known alkaloids (3–21) were isolated from the roots of Aconitum coreanum (Lèvl.) Rapaics, which is the raw material of a new approval anti-arrhythmia drug “Acehytisine Hydrochloride”. The structures of isolated compounds were established by means of 1D, 2D NMR spectroscopic and chemical methods. All isolates obtained in the present study were evaluated for their inhibitory effects on blocking the ventricular specific sodium current using a whole-cell patch voltage-clamp technique. Among these 21 compounds, Guan-Fu base S (GFS, 3) showed the strongest inhibitory effect with an IC50 value of 3.48μM, and only hetisine-type C20 diterpenoid alkaloids showed promising IC50 values for further development. [Copyright &y& Elsevier]

Abstract: Two novel protosappanins, named Caesappin A (1) and B (2), along with three known protosappanins were isolated from Caesalpinia sappan L. Caesappin A is a new type protosappanin with a seven-membered ring fusing an acetal-type section. Compound 4 was isolated from the genus Caesalpinia for the first time. The structures were elucidated on the basis of spectral analysis and the absolute configuration was determined by the ECD experiment coupled with calculated ECD spectra. Their cytotoxic activities were evaluated using MTT assay. [Copyright &y& Elsevier]

Abstract: Four new limonoids (1–4), together with five known limonoids (5–9), were isolated from the fruits of Melia toosendan. Their structures were elucidated based on extensive spectroscopic analyses (1D- and 2D-NMR, HRESIMS, IR, [α]D). The isolated compounds were evaluated for their neurite outgrowth-promoting activities. Compounds 2 and 6 significantly enhanced NGF-mediated neurite outgrowth in PC12 cells at concentrations ranging from 0.1 to 50.0μM. [Copyright &y& Elsevier]

Abstract: A new degraded limonoid, named isodictamdiol A (1), two known degraded limonoids (2, 3) and a new nature product of quinoline alkaloid (4) along with five known quinoline alkaloids (5–9) were isolated from the root bark of Dictamnus angustifolius G. Don ex Sweet.. Certain useful NMR data were generalized to determine the structures of compounds 1 and 4. The structural elucidation of Compound 4 was first reported herein. Compounds 1–9 showed significant inhibitory effects on platelet aggregation induced by ADP at 250μM, while Compound 4 showed potent anti-platelet aggregation activity. [Copyright &y& Elsevier]

The genus Clerodendrum Linn., originally belonging to Verbenaceae, was assigned to Lamiaceae by APG (Angiosperm Phylogeny Group) Ⅱ. Seven abietane diterpenoids ( 1 –7) along with three anthraquinones ( 8 – 10 ) and one neolignan (11 ) were isolated and identified from the stems of Clerodendrum trichotomum Thunb.. Among them, compounds 4 , 6 and 8 – 11 were reported from the genus Clerodendrum Linn. for the first time. Compounds 1 , 3 and 7 were obtained from this species for the first time. Isolation of abietane diterpenoids from C. trichotomum could further comfirm that the genus Clerodendrum belongs to Lamiaceae rather than Verbenaceae. [ABSTRACT FROM AUTHOR]